Growth promoting preparations for plants



May 26, 1953 H. vELDsTRA 2,639,983

GROWTH PROMOTING PREPARATIONS lFOR PLANTS Filed April so, 194s 2 Sheets-Sheet l YVYYY 11 Y? e VVVVY 7 VVYVV 6 TMW 5 T wm w. m

May 26, 1953 H. vELDsTRA 2,639,983

GROWTH PROMQTING PREPARATIONS FOR PLANTS Filed April 30, 1949 2 Sheets-Sheet 2 5 6 7 8 hqvnaphtyhcekic acid 4. a. 0.4.10 mol/litre Patented May 26, 1953 Haaye Veldstra," Amsterdam, Netherlands, as-

signor to N. V. Amsterdamsche Chninefabriek, Amsterdam,` North Holland, Netherlands, a

company of the Netherlands Applicationl April 30, 1949, Serial o. 90,752 ,In the NetherlandsMay 3, 1948 This invention relates to'improvements in the manufacture of growth promoting preparations' for plants. v

Up to the present'time the compounds which are highly `active growth promoting substances for plants have almost exclusively been used singly,`for any given application those individual compounds having been selected which yield the maximum effect in that application. Thus, in thecase of the root formation of cuttings, indoleacetic acid, indole-butyric acid and naphthylacetic acid are used and forthe induction of parthenocarpy preferably -naphthoxyacetic acid or 2:4-dichloro-phenoxyacetic acid (in very low concentrations), while the premature dropping offruit is prevented with solutions of the potassium salt of naphthylacetic acid. It may be mentioned that the undesirable sprouting of stored potatoes may be prevented with naphthylacetic acid methyl ester, and that certain weeds are combatted with 2t4-dichloro-phenoxyacetic acid (in higher concentrations). l

Theactivity of mixtures of the more highly active growth promoting substances has not so far been studied to any great extent (cf. Hitchcock and Zimmermann, Contrib. Boyce Thomp. Inst. 1l, 143 (1940) and in practice such mixtures have not yet gainedy anyparticular importance. `In 1939 ,Went(Pr oc, Kon. Akad. ,Wetensch Amsterdam 42, 581, 731. (1939)) reported that inthe pea testa preliminary treatment with solutions of phenylbutyric acid has 'fora result that smaller quantities of-an vactive compound,`

such` as indole-acetic acidor naphthylacetic ac'id.

are sufficient in order to attain a givengrowth;

promoting eiiect, while" the activity of weak growth promoting substancessuch as vindoleprponic acid or cis-cinnamic acid, can be in- .v

creased by this preliminary treatment. Phenyl butyric acidA perv se has-no growth Vpromoting effect.

Went used this compound in a concentration. which Wasrather `.high for vthe vpea test 4(100M.

mg./litre='60X10-5mol/litre) `Skoog (Am. J. Bot. 29,568

cylinder test, and concludedthat'in the concentrationregion examined byhim it is chieiiy-a checking of theA indole-acetic acid eifect.-` whichA f occurs ,-(vide the ASummary on page 575).

The present invention is based on the observas (1942))fexahindfthe effect of l mixturesy of indole-acetic ,acidand phenylbutyric acid` in theAvena .test and. in .the

i 9 claims.` (o1. 'zr- 2.5)

moting'substances. The carboxylic acids which act as synergists which acts asV a synergist, namely a monocarboiiylic acid differing from the growth promoting substance used, which acid contains an aliphatic, hydro-aromatic, aromatic or araliphatic hydrocarbon radical such that the total number of carbon atoms in the molecule is 10-16 in the effect.V .As appears from the tests, the optimum of the activity of these synergists lies at a molecular size corresponding to 11-14 carbon atoms;

`the compounds having a total number of 11 or 12 carbon atoms' in the molecule were found to be the most eective. Preparations comprising lower carboxylic acids of the indole series in conjunction with such of the naphthalene and/or y anthracene series are excluded.

`This surprising synergetic effect is turned to account in accordance vwith the present in two ways. Y

According to one feature of the present invention a `growth promoting preparation comprises a synergist of ther type described incorporated with one; of the more highly active growthrpromoting substances, that is a substance the activity of which is such as to have hitherto justified its use alone. In this case a more highly active rgrowth promoting substance can be used in a 'considerably' lower concentration thanvis otherwise required for an optimum effect, the addition of Va carboxylic acidofthe group referred to havingthe effect that the activity of the preparation as a whole is brought to a level which may even` be higher than the maximum' that can be attainedwith the growth promoting substance alone. s

According to a further feature of the invention a growthipromoting preparation comprises a synergist of the type described incorporated with a weakgrowth promoting substance, that is a substance not having suicient growth promoting activity to justify its use along in normal circumstances. In `this case the effect. of the growth promoting substances which by themselves are of low activity is enhanced with the production again of highly active preparations.

In both cases a considerable economy can be effected. `In general it is the highly active growth promoting substances which are most difficult to produce. As a rule thesynergists can be produced more readily than the highly active growth pro- The compounds used as synergists havev invention branched fatty acids particular mention may be made of substituted acetic acidsy such as di-namylacetic acid, din-hexylacetic Vacid,"din heptylacetic acid, tri-n-propylacetic acid, and their isomers, and also those with a partial cy-clic structure (isocyclic, including aromatic), e. g. dibenzylacetic acid. Some other examples are: di-n-butylacetic acid, di (2 methyl butyl 1) acetic acid, di-(B-methyl-butyl-l) ,acetic acid,

di- (cyclohexyl-methyl) acetic acid.

4 in a concentration of 4X 10-5 moles/litre. In experiments 6, 7 and 8: a solution of a-naphthyl acetic acid in a concentration of 1 10*5, 0.4 1K)5 and 0.1 10-5 moles/litre respectively, each in combination with dii-n-amyl acetic acid in a concentration of 4 105 moles/litre.

The activity of each of the foregoing solutions is investigated by means of the well-known pea test, the results of which are shown on the drawings. i

In Fig. 1 experiments 2 and 6, 3 and 7, 4 and 8 should be compared. Experiment 1 shows the activity of a-naphthyl acetic acid in a concentration of 4 105 moles/litre. It follows from a comparison of experiments 1 and 6 that a combination of a-naphthyl acetic acid in a concentration of 1 10-5 mol/litre and di-n-amylacetic Of particular value as synergists are organic"- monocarboxylic acids as above specified the moF lecular size of which is of the same order as that ofthe highly active .growthpromoting substances.

Growth promoting componentsof the mixtures to be produced according tothe inventionmay be, for example: highly active growth promoting substances, such as indole-acetic acid, indole.- butyric acid, naphthylacetic acid or dichlor-2:l phenoxyacetic acid; or growth promoting substances which are less active, e. g. naphthylb utyric a-cids, indole-propionic acid or phenylacetic acid. Various derivatives of these substances, such as salts (for example the alkali metal or. ammonium salts), esters (for example the methyl or ethyl esters) and amides, can also be used.

AThe synergists can also be used in the form vof derivatives substituted in the carboxyl group. The choice dependsv e. g. as salts, amides, esters. on the purpose for which the preparation according to the invention is to be used. vThe proportion between the concentrations of growth promoting substance and synergist may vary within wide limits. In general it is to be preferred to ascertain by means of a test what proportion of the components is most desirable for the given substances and for a given purpose. Excellent results have been attained, for example, with a: mol/litre of synergist with the use of a: to 0.05m mol/litre of growth promoting substance in those cases where the growth promoting substance alone would be used in a concentration of .r mol/litre or more. From this it may also be concluded that the order of the concentration of the preparations may be approximately identical with that which is used in the case of the growth promoting substances alone. The mixtures may be applied in the .usual manner. i. e. for example in solution (for. exam.-

ple in an aqueous solution) or on a solid carrier` (for example on talcum or vbolus alba) they can also be sprayed as aerosols.

The accompanying drawings illustrate the resultsof tests set forth in the mentioned exam ples.

In the drawings:

Fig. 1 shows the results of Example I and Fig. 2 shows the results of Example II.

Referring to the drawings and the legends thereonin detail, and iirst to the showing in Fig.` 1, the solutions employed in the experiments are as follows:

In experiments designated 1, 2, 3 and 4: a solution of a-naphthyl acetic acid in a concentration of 4 105, 1x10-5, 0.4X10-5 and 0.1 l*5 moles/litre respectively. In experiment designated 5: a solution of di-n-amylacetic acid acid in a concentration of 4 10*5 mol-litre has a greater activity than a-naphthyl acetic acid alone in a concentration of 4 105 mol-litre. The activity of the solutions in lexperiments 1 and'lis about the same. y if Experiment 5 shows that the synergist di-namyl acetic acid has no appreciable activity in the pea test, if any.

In Fig. 2 experiments 1 and 2, 3 and 4, 5 and 7, '7 and 8 should be compared, the even numbers showing the influence of the synergist.

The solutions employed in the experiments illustrated in Fig, 2 are as follows:

In experiments designated 1, 3, 5 and 7: ya solution of a-naphthyl acetic acid in a concentra-,-

tion of 4X10-5, 2X10*5, 1x10-5 and 0.4X10. moles/ litre respectively.

In. experiments designated 2, 4, 6 and 8: a solution of a-naphthyl acetic acid in a concentra- The examples previously referred to which i1- lustrate the invention are as follows:

Example I For purposes of comparison solutions in water were made of a-naphthylacetic acid in concentrations of 4, 1, 0.4 and 0.1)(10"5 mol/litre. and a .solution of di-n-amylacetlc acid in a concentration of 4 105 mol/ litre.

APreparations according to the present invention were made consisting of such mixtures of a-naphthylacetic,acid and di-n-amylacetic acid as contain 1, 0.4 and 0.1 105 mol/litre o1 naphthylacetic acid and in each case 4 10s mol/litre of di-n-amylacetic acid. In the socalled pea test the activities of these solutions were compared. It was found that whereas the solution of 0.1 105 mol/litre of naphthylacetic acid alone is only very slightly active (4)(10-5 mol/litre is the optimum in this case) and di-namylacetic acid itself has no growth promoting effect in the above concentration, of the mixed solutions even that containing the smallest of the above quantities proved to have at least the same activity as a-naphthylacetic acid alone in a concentration 40X stronger, and was found to exceed this activity in some cases. This can be seen from Fig. 1.

Example II Corresponding .tests were carried out with solutions of a-naphthylacetic acid as growth promoting substance in concentrations of 4, 2, 1 and 0.4)(10-5 mol/litre, a solution of decalylacetic acid in a concentration of 4 105 mol/litre, and solutions according to the present invention of such mixtures of a-naphthylacetic acid and decalylacetic acid as synergist as contained 4, 2, 1 and 0.4 l0*5 mol/litre of a-naphthylacetic acid and in each case 4 105 mol/litre of decalylacetic acid.

It is well known that the synergists are less expensive than the growth substances.

It was found in all cases that the solution containing the mixture of growth promoting substance and synergist was appreciably more active than the solution of the same concentration of the growth promoting substance alone. The mixed solution with the lowest concentration of a-naphthylacetic acid was appreciably more active than the most concentrated solution of the said growth promoting substance alone. This can be seen from Fig. 2.

What 1 claim is:

1. A preparation for promoting plant growth comprising a substance having the capacity to promote plant growth chosen from the group consisting of indole acetic acid, indole butyric acid, naphthyl acetic acid, dichloro2,4phenoxy acetic acid and naphthyl butyric acid with which is incorporated a compound chosen from the group consisting of a dialkyl acetic acid, its alkalimetal salts, its ammonium salt, its amide and its esters such that the total number of carbon atoms of the acid is 10-16.

2. A preparation as claimed in claim 1 in which the substance having the capacity to promote plant growth consists of indole acetic acid.

3. A preparation as claimed in claim 1 in which the substance having the capacity to promote plant growth consists of indole butyri'c acid.

4. A preparation as claimed in claim 1 in which the substance having the capacity to promote plant growth consists of naphthyl acetic acid.

5. A preparation as claimed in claim 1 in which the substance having the capacity to promote plant growth consists of dichiaro-2,4- phenoxy acetic acid.

6. A preparation as claimed in claim 1 in which the substance having the capacity to promote plant growth consists of naphthyl butyric acid.

7. A preparation as claimed in claim 1 in which the ratio of the substance having the capacity to promote plant growth to the said compound incorporated therewith is from (0.05-1) to 1, calculated in moles.

3. A preparation as claimed in claim 1 in aqueous solution.

9. A preparation as claimed in claim 1 on a solid carrier.

HAAYE VELDSTRA.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 2,284,970 Avery June 2, 1942 2,289,974 Leiby July 14, 1942 2,394,916 Jones Feb. 12, 1946 2,446,836 King Aug. 10, 1948 OTHER REFERENCES Article by Went in Proc. Kon. Akad. Wetensch. Amsterdam, vol. 42, pages 581, 731 (1939).

Contrib. Boyce Thompson Inst.-vo1. 10 (July- September 1939), pages 481 to 508. 

1. A PREPARATION FOR PROMOTING PLANT GROWTH COMPRISING A SUBSTANCE HAVING THE CAPACITY TO PROMOTE PLANT GROWTH CHOSEN FROM THE GROUP CONSISTING OF INDOLE ACETIC ACID,INDOLE BUTYRIC ACID, NAPHTHYL ACETIC ACID, DICHLORO-2,4-PHENOXY ACETIC ACID AND NAPHTHYL BUTRIC ACID WITH WHICH IS INCORPORATED A COMPOUND CHOSEN FROM THE GROUP CONSISTING OF A DIALKYL ACETIC ACID ITS ALKALIMETAL SALTS, ITS AMMONIUM SALT, ITS AMIDE AND 